We retrospectively reviewed the medical records of 97 children (59 boys and 38 girls) with a median age of 13 +/- 4 years who had been treated with continuous infusion of doxorubicin at a dosage of 60 mg/m2 over 24 h (61 patients) or at a dosage of 75 mg/m2 over 72 h (36 patients). The drug was administered every 3 weeks. The cardiac status of patients was evaluated as a baseline and every 6 months during, and following therapy (median, 30.5 months). The evaluations included M-mode and two-dimensional echocardiography. Congestive heart failure developed in only one patient in this series, an 8-year-old girl who ultimately died of her cardiac complication. This incidence of doxorubicin-induced cardiotoxicity was compared with that seen in a control group of pediatric patients previously treated with doxorubicin at similar dosages but with a rapid infusion. The result compared favorably to the 13% incidence of cardiotoxicity (p = 0.03) and 7% mortality (p < 0.01) in the control group. No changes in the levels of tumor response were noted in children treated by continuous infusion when compared with historical controls. Continuous-infusion schedules of doxorubicin thus result in fewer incidences of cardiotoxicity in children and should be considered for wider application in pediatric cancer patients receiving doxorubicin.